Open AccessNew family of graphene-based organic semiconductors: An investigation of photon-induced electronic structure manipulation in half-fluorinated graphene
Author(s) -
Andrew L. Walter,
Hasan Şahin,
Jun Kang,
KiJoon Jeon,
Aaron Bostwick,
Şeyda Horzum,
Luca Moreschini,
Young Jun Chang,
F. M. Peeters,
Karsten Horn,
Eli Rotenberg
Publication year - 2016
Publication title -
physical review. b./physical review. b
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.78
H-Index - 465
eISSN - 2469-9969
pISSN - 2469-9950
DOI - 10.1103/physrevb.93.075439
Subject(s) - graphene , fermi level , band gap , materials science , substrate (aquarium) , electronic structure , angle resolved photoemission spectroscopy , condensed matter physics , electronic band structure , physics , nanotechnology , quantum mechanics , electron , oceanography , geology
The application of graphene to electronic and optoelectronic devices is limited by the absence of reliable semiconducting variants of this material. A promising candidate in this respect is graphene oxide, with a band gap on the order of ∼5eV, however, this has a finite density of states at the Fermi level. Here, we examine the electronic structure of three variants of half -fluorinated carbon on Sic(0001), i.e., the (6√3×6√3) R30° C/SiC "buffer layer," graphene on this (6√3×6√3) R30° C/SiC buffer layer, and graphene decoupled from the SiC substrate by hydrogen intercalation. Using angle-resolved photoemission, core level photoemission, and x-ray absorption, we show that the electronic, chemical, and physical structure of all three variants is remarkably similar, exhibiting a large band gap and a vanishing density of states at the Fermi level. These results are explained in terms of first-principles calculations. This material thus appears very suitable for applications, even more so since it is prepared on a processing-friendly substrate. We also investigate two separate UV photon-induced modifications of the electronic structure that transform the insulating samples (6.2-eV band gap) into semiconducting (∼2.5-eV band gap) and metallic regions, respectively